Fluid dispensing device

ABSTRACT

A fluid dispensing device having a barrel having a lumen for containing a fluid therein and a flexible structure extending from the barrel. A plunger is axially slidable within the lumen to dispense fluid from the barrel, the plunger having a first set of grooves spaced apart a first distance and a second set of grooves spaced apart a second distance. The flexible structure includes a flexible arm extending transversely with respect to the barrel and configured to engage the grooves.

This application claims priority from provisional application62/357,952, filed Jul. 2, 2016, the entire contents of which areincorporated herein by reference.

BACKGROUND Technical Field

This application relates to a fluid dispensing device, and, moreparticularly, to a fluid dispensing device for supplying select doses offluid.

Background of Related Art

Devices for drawing and administering predetermined amounts or dosagesof fluid are widely used in a variety of industries including, but notlimited to, medicine. Dosage devices, such as hypodermic syringes,administer the drug directly in the bloodstream or in the tissue of thepatient, who is thus directly affected by the drug. As a result, it isvery important to assure that the precise dosage is administered at alltimes.

Commonly, hypodermic syringes include a graduated scale disposed on thebody of the syringe. Utilizing the scale, an individual administering adrug will draw a quantity of the drug from a vial into the syringe, andthen expel quantities of the drug until the precise dosage is achieved.This common measurement procedure can often be difficult andtime-consuming, and more importantly, can be quite wasteful, as aquantity of the drug is often discarded in order to achieve theappropriate dosage. Other syringes are provided to hospitals orclinicians pre-filled. Still, the user relies on the scale or markingson the syringe to deliver the appropriate doses.

Quite often, medical professionals administering an injection may nothave a clear view of the targeted body part of the patient. In thiscase, many rely on their experience to administer the desired dosage,which still may not be precise. Furthermore, those individuals whoself-administer drugs may experience even more inconvenience that theprofessionals. Diminished hearing, eyesight and/or diminished dexterityof the user may lead individuals to draw or dispense an imprecise dosageof the drug into, or from the syringe. More significantly, it may leadthem to draw or dispense an insufficient or excessive dosage into theirbody, which can result in life-threatening or worse, fatal,consequences.

Attempts have been made in the prior art to overcome these problems andprovide some type of structure, which allows a person to accuratelytransfer the amount of medication to and from a syringe.

U.S. Pat. No. 4,252,159 to Maki teaches a dosage device including anelongated slat body on which a syringe is mounted by means of upstandingsubstantially Y-shaped brackets that are spaced from one another andextend upwardly from a flat exposed surface of the body. An adjustabletop member threadedly engages an upstanding internally threaded elementprovided with externally located lands that, in turn, co-operate with anirregularly shaped knob so as to produce audible signals upon 360°revolution. The engagement and sound between the above-mentionedelements depends upon a number of factors which may include flexibilityof the base or play between the threaded engagement such that theoutwardly projected portion of the knob may pass over and in engagementwith the lands.

U.S. Pat. No. 4,466,426 to Blackman discloses a syringe that has aplunger providing an audible sound upon a plunger being withdrawn fromthe barrel of a syringe.

U.S. Pat. No. 4,883,101 to Strong discloses a device for filling aninjection syringe which incorporates a sound indicator provided withmechanical, electrical or an electronic sound device. A spring-loadedball bearing is biased against a gear wheel and produces a distinctlyaudible clicking sound when the gear moves a single notch. A user countsthe sounds accurately indicating the amount of liquid medicine drawninto the syringe when the attached syringe holder moves.

U.S. Pat. Nos. 5,741,232 and 5,795,333 to Reilly disclose a frontloading syringe having a movable plunger rotatable on an injectorhousing. An audible indicating mechanism is activated when the syringeis essentially in the desired mounted position and includes ribs whichfunction as volumetric gradations.

While the above noted patents are all directed to structures whichattempt to overcome problems associated with dispensing proper dosage ofmedicine, these structures are rather complicated and inconvenient inuse. The need therefore arises to have a simple structure of a dosingdevice that will allow a user to administer medicine in a simple andefficient manner.

Furthermore to minimize the aforementioned inconveniences, some of theknown dosage devices have been provided with a tactile mechanismoperative to generate a sound signal and/or increased resistanceindicating displacement of the desired dosage of fluid into and from thedosage device.

U.S. Pat. Nos. 6,579,269 and 7,901,384 disclose syringes which attemptto provide a structure configured to reliably produce a distinct audibleand tactile signal to the user indicating that the desired dosage offluid has been drawn into, or displaced from, the dosage devices in areliable, simple fashion. Although these patents disclose such signalsto indicate dosage increments, their versatility is limited. This addsto the expense of the syringes and limits the manufacturer's ability toprovide varied assortment of syringes tailored to applying predeterminedor carefully controlled amounts of fluid.

It would be advantageous to provide syringes which facilitate adaptationto varied dosage needs in an efficient, reliable and cost effective way.

SUMMARY

The present invention provides in one aspect a fluid dispensing devicehaving a barrel having a lumen for containing a fluid therein and aflexible structure extending from the barrel. A plunger is axiallyslidable within the lumen to dispense fluid from the barrel, the plungerhaving a first set of grooves spaced apart a first distance and a secondset of grooves spaced apart a second distance. The flexible structureincludes a flexible arm extending transversely with respect to thebarrel and positioned to engage either the first set of grooves or thesecond set of grooves.

In accordance with another aspect, the present invention provides afluid dispensing device comprising a barrel having a lumen forcontaining a fluid therein, a flexible structure extending from thebarrel, and a plunger axially slidable within the lumen to dispensefluid from the barrel. The plunger has a first set of grooves and asecond set of grooves and a first position wherein the flexiblestructure is engageable with grooves of the first set of grooves whenthe plunger is advanced through the barrel and a second position whereinthe flexible structure is engageable with grooves of the second set ofgrooves when the plunger is advanced through the barrel.

In accordance with another aspect of the present invention a fluiddispensing device is provided comprising a barrel having a lumen forcontaining a fluid therein, a flexible structure extending from thebarrel and a plunger axially slidable within the lumen to dispense fluidfrom the barrel. The plunger has a first wall having a first set ofgrooves, a second wall having a second set of grooves, and a third wallbetween the first and second walls. The plunger has a first orientationand a second orientation, wherein a) in the first orientation theflexible structure is engageable with the first set of grooves and thesecond set of grooves when the plunger is advanced axially within thebarrel and b) in the second orientation the flexible structure is notengageable with the first set of grooves or the second set of grooveswhen the plunger is advanced axially through the barrel.

In accordance with another aspect, the present invention provides afluid dispensing device comprising a barrel having a lumen forcontaining a fluid therein and a flexible structure extending from thebarrel, the flexible structure having a first arm and a second arm, anda plunger axially slidable within the lumen to dispense fluid from thebarrel. The plunger has a first wall having a first set of groovesspaced apart a first distance and a second wall having a second set ofgrooves spaced apart a second distance different than the firstdistance, the first arm having a first stiffness and the second armhaving a second stiffness. The first arm is engageable with the firstset of grooves and the second arm is engageable with the second set ofgrooves, wherein the first arm provides feedback to the user differentthan feedback provided by the second arm.

In accordance with another aspect, the present invention provides afluid dispensing device comprising a barrel having a lumen forcontaining a fluid therein and a plunger axially slidable within thelumen to dispense fluid from the barrel, the plunger having anasymmetrical transverse cross-sectional dimension having a first walland a second wall. The first wall has a first set of grooves spacedapart a first distance and the second wall has a second set of groovesspaced apart a second distance different than the first distance. Aflexible structure is mountable to the barrel and has a first arm and ismountable to the barrel in a select orientation so that the first arm isengageable with either the first set of grooves or the second set ofgrooves.

In accordance with another aspect, the present provides a fluiddispensing device comprising a barrel having a lumen for containing afluid therein and a deflectable structure extending from the barrel anda plunger axially slidable within the lumen to dispense fluid from thebarrel, the plunger having a longitudinal axis and a set of groovesextending longitudinally along an outer surface. The deflectablestructure extends transversely with respect to the barrel and positionedto engage the set of grooves and deflects in a transverse direction todisengage from the grooves.

In accordance with another aspect of the present invention, a fluiddispensing device is provided comprising a barrel having a lumen forcontaining a fluid therein and a deflectable structure extending fromthe barrel, the deflectable structure including first and second arms,wherein the first arm has a first proximal surface and the second armhas a second proximal surface. The first and second arms are spacedapart so that the first and second proximal surfaces are not contiguous.A plunger is axially slidable within the lumen to dispense fluid fromthe barrel and has a longitudinal axis and a set of grooves extendinglongitudinally along an outer surface. The first and second arms extendtransversely with respect to the barrel and positioned to engage the setof grooves.

In accordance with another aspect, the present invention provides afluid dispensing device comprising a barrel having a lumen forcontaining a fluid therein and a deflectable structure extending fromthe barrel, the deflectable structure including a first arm having afirst proximal portion and a first distal portion. A plunger is axiallyslidable within the lumen to dispense fluid from the barrel, the plungerhaving a longitudinal axis and a set of grooves extending longitudinallyalong an outer surface. The deflectable structure extends transverselywith respect to the barrel and positioned to engage the set of grooves,wherein the first arm is configured such that the distal portiondeflects to a greater degree than the proximal portion as the firstflexible arm disengages from the groove.

In accordance with another aspect, the present invention provides afluid dispensing device comprising a barrel having a lumen forcontaining a fluid therein and a deflectable structure extending fromthe barrel, the deflectable structure including a first arm having afirst proximal portion and a first distal portion. A plunger is axiallyslidable within the lumen to dispense fluid from the barrel, the plungerhaving a longitudinal axis and a set of grooves extending longitudinallyalong an outer surface. The deflectable structure extends transverselywith respect to the barrel and positioned to engage the set of grooves,wherein the distal portion and the proximal portion of the first arm aredeflectable as the first arm disengages from the groove.

In accordance with another aspect, the present invention provides afluid dispensing device comprising a barrel having a lumen forcontaining a fluid therein and a flange. A plunger is axially slidablewithin the lumen to dispense fluid from the barrel, the plunger having alongitudinal axis and a set of grooves extending longitudinally along anouter surface. A deflectable structure is mountable to the proximalportion of the barrel and is engageable with an underside of the flange,the deflectable structure extending transversely with respect to thebarrel and positioned to engage the set of grooves, the deflectablestructure being external of the barrel and exposed.

In accordance with another aspect, the present invention provides a kitfor dispensing fluid comprising a) a plunger positioned within a barrelcontaining a fluid therein, the plunger having an asymmetricalcross-sectional dimension having a first wall and a second wall, thefirst wall having a first set of grooves spaced apart a first distanceand the second wall having a second set of grooves spaced apart a seconddistance different than the first distance, and b) a mounting structureslidable over the plunger and mountable to the barrel, the mountingstructure having a flexible member for engagement with one of the setsof grooves during advancement of the plunger to dispense fluid.

In accordance with another aspect, the present invention provides amethod of assembling a syringe comprising:

mounting a plunger within a barrel, the plunger having at least one setof grooves extending along an exterior surface;

sliding a mounting structure over the plunger, the mounting structureincluding a flexible arm configured for engagement with the grooves ofthe plunger during axial advancement of the plunger;

attaching the mounting structure to the barrel; and mounting a pressingsurface onto a proximal end of the plunger.

In accordance with another aspect, the present invention provides amethod for delivering select doses of fluid to a patient comprising:

providing a fluid dispensing device having a barrel and a plungerslidable axially within a lumen of the barrel, the plunger having afirst set of grooves and a second set of grooves;

selecting the set of grooves to be engaged by a flexible element of thefluid dispensing device; and

advancing the plunger such that the flexible element engages the groovesof the selected set of grooves thereby providing feedback for fluiddelivery of an amount corresponding to a distance between the grooves ofthe selected set of grooves.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiment(s) of the present disclosure are described hereinwith reference to the drawings wherein:

FIG. 1 is a front view of one embodiment of the fluid dispensing device(syringe) of the present invention;

FIG. 2 is a side view of the fluid dispensing device of FIG. 1; FIG. 3is an exploded perspective view of the fluid dispensing device of FIG.1;

FIG. 4 is a top view of the fluid dispensing device of FIG. 1;

FIG. 5 is a detailed view of the indicated area A of FIG. 2;

FIG. 6 is a cross-sectional view taken along line B-B of FIG. 1;

FIG. 7 is a detailed view of the indicated area C of FIG. 3;

FIG. 8 is a front view of an alternate embodiment of the fluiddispensing device of the present invention;

FIG. 9 is a side view of the fluid dispensing device of FIG. 8;

FIG. 10 is an exploded perspective view of the fluid dispensing deviceof FIG. 8;

FIG. 11 is a top view of the fluid dispensing device of FIG. 8;

FIG. 12 is a detailed view of the indicated area D of FIG. 9;

FIG. 13 is a cross-sectional view taken along line E-E of FIG. 8;

FIG. 14 is a front view of another alternate embodiment of the fluiddispensing device of the present invention;

FIG. 15 is a side view of the fluid dispensing device of FIG. 14;

FIG. 16 is an exploded perspective view of the fluid dispensing deviceof FIG. 14;

FIG. 17 is a detailed view of the indicated area F of FIG. 14;

FIG. 18 is a cross-sectional view taken along line G-G of FIG. 14;

FIG. 19 is a front view of another alternate embodiment of the fluiddispensing device of the present invention;

FIG. 20 is a side view of the fluid dispensing device of FIG. 19;

FIG. 21 is an exploded perspective view of the fluid dispensing deviceof FIG. 19;

FIG. 22 is a detailed view of the indicated area H of FIG. 19;

FIG. 23 is a cross-sectional view taken along line J-J of FIG. 20;

FIG. 24 is a top view of the fluid dispensing device of FIG. 19;

FIG. 25 is a front view of another alternate embodiment of the fluiddispensing device of the present invention;

FIG. 26 is a side view of the fluid dispensing device in the position ofFIG. 25;

FIG. 27 is a top view of the fluid dispensing device in the position ofFIG. 25;

FIG. 28 is an exploded perspective view of the fluid dispensing deviceof FIG. 25;

FIG. 29 is a cross-sectional view taken along line L-L of FIG. 25;

FIG. 30 is a detailed view of the indicated area K of FIG. 26;

FIG. 31 is a front view similar to FIG. 25 showing the plunger rotatedto a second orientation for non-engagement of the plunger grooves;

FIG. 32 is a side view of the fluid dispensing device in the position ofFIG. 31;

FIG. 33 is a top view of the fluid dispensing device in the position ofFIG. 31;

FIG. 34 is an exploded perspective view of the fluid dispensing devicein the position of FIG. 31;

FIG. 35 is a cross-sectional view taken along line N-N of FIG. 31;

FIG. 36 is a detailed view of the indicated area M of FIG. 32;

FIG. 37 is a front view of another alternate embodiment of the fluiddispensing device;

FIG. 38 is a side view of the fluid dispensing device of FIG. 37;

FIG. 39 is a detailed view of the indicated area P of FIG. 38;

FIG. 40 is a front view of a proximal portion of another alternateembodiment of the fluid dispensing device of the present invention;

FIG. 41 is a side view of the fluid dispensing device of FIG. 40;

FIG. 42 is a top view of the fluid dispensing device of FIG. 40;

FIG. 43 is a perspective view of the plunger of the fluid dispensingdevice of FIG. 40;

FIG. 44 is a top view of the fluid dispensing device of FIG. 40 showingthe plunger in line with the barrel tabs for engagement of the flexiblearms of the feedback mechanism with a first set of plunger grooves;

FIG. 45 is a top view of the fluid dispensing device of FIG. 40 showingthe plunger tabs perpendicular to the barrel tabs for engagement of theflexible arms of the feedback mechanism with a second set of plungergrooves;

FIG. 46 is a side view of the proximal portion of the plunger and barrelin the plunger position of FIG. 44;

FIG. 47 is a side view of the proximal portion of the plunger and barrelin the plunger position of FIG. 45;

FIG. 48 is an exploded view of another alternate embodiment of the fluiddispensing device of the present invention;

FIG. 49 is a detailed view of the indicated area R of FIG. 48;

FIG. 50 is a detailed view of the indicated area S of FIG. 48;

FIG. 51 is a front view of the proximal portion of the device of FIG.48;

FIG. 52 is a cross-sectional view taken along line T-T of FIG. 51;

FIG. 53 is a side view of a proximal portion of a fluid dispensingdevice of an alternate embodiment; and

FIG. 54 is a side view similar to FIG. 53 showing the plunger furtheradvanced into the barrel.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The present invention is directed to fluid dispensing devices thatprovide feedback to the user to enable incremental delivery of a fluidfrom the fluid dispensing device. The devices of the various embodimentsdisclosed herein include a barrel containing the fluid, a plungeraxially slidable within the barrel to deliver the fluid from the barreland a feedback mechanism to indicate to the user the progression of theplunger within the barrel and the doses of fluid administered. Thefeedback mechanism provides a tactile and/or an audible indicator to theuser to enable effective advancement of the plunger in increments toprovide desired doses of fluid from the barrel, and better control ofsuch incremental fluid delivery. In some embodiments, the barrel isformed with the plunger engaging mechanism which provides the feedbackmechanism; in other embodiments the plunger engaging mechanism isattached to a standard barrel. In either of these versions, modularityis provided to decrease the cost of manufacture and enable standardsyringes to be easily modified to add on the feedback mechanism of thepresent invention.

Additionally, to accommodate the user's desire to select optimaldelivery doses, in some embodiments disclosed herein, the feedbackmechanism is designed to provide varied doses within a single syringe.Various exemplary embodiments are discussed below.

As used herein, the term proximal refers to regions closer to the userand the term distal refers to regions further from the user. Further,the terms fluid dispensing device and syringe are used interchangeably.The fluids that can be administered include gels for cosmetic surgeries,insulin, therapeutic agents such as chemotherapy agents, and any otherinjectable fluids.

Turning now to the drawings wherein like reference numerals correspondto the same elements throughout the drawings and turning first to FIGS.1-7, one embodiment of the dispensing device or syringe is illustratedand designated generally by reference numeral 11. The dispensing device11 includes a barrel 2, a plunger 4 and a feedback mechanism 10. Thebarrel 2 includes a lumen formed therein to receive fluid for deliveringto a patient and markings 5 along its length to provide a visualindication to the user of the amount of fluid contained within thebarrel 2. Penetrating needle 14 extends distally from a distal end 3 ofthe barrel 2. The plunger 4 is received in barrel 2 for axially slidablemovement distally to dispense the fluid from the barrel 2. A pluralityof grooves 12 are formed in an outer (external) surface of the plunger 4along its length, spaced apart at intervals or increments correspondingto the amount of fluid desired to be injected at each step ofadvancement of the plunger 4 within the barrel 6. The grooves 12 canextend along a partial length or the entire length of the plunger. Inthe illustrated embodiment, the plunger grooves 12 are equidistantlyspaced apart to provide equal doses of fluid. However, it is alsocontemplated that in alternate embodiments, the spacing between groovescould be non-uniform to accommodate situations where it is desired toprovide larger or smaller doses at certain times during injection. Also,the distances between the grooves can be greater or less than thedistances shown in the Figures to provide variations on dosage delivery.Examples of spacings between grooves can be 0.1 cc, 0.5 cc, 1 cc, etc.(Such examples can also be used with the other embodiments disclosedherein). Other spacings are also contemplated. The grooves are spaced atintervals corresponding to a predetermined dose of fluid from thebarrel. Although the grooves are shown substantially perpendicular tothe longitudinal axis of the plunger they can alternatively be placed atother angles to the longitudinal axis.

Feedback mechanism 10 includes a flexible structure 8 having a pair offlexible arms 10 a, 10 b engageable with plunger grooves 12. Arms 10 a,10 b are external of barrel 2. They can be exposed and visible to theuser as shown. Arms 10 a, 10 b extend proximally from a proximal end 7of the barrel 2 and then bend inwardly toward the longitudinal axis ofthe device. Thus, the arms 10 a, 10 b form two somewhat U-shaped memberswith one leg, i.e., the distal leg, of the U extending transversely fromcap or support 13 and the other leg, i.e., the proximal leg, extendingtransversely toward the longitudinal axis to engage one of the grooves12 on the plunger 4 and the base of the U extending longitudinally.Thus, the two transverse legs of arms 10 a, 10 b extend toward oneanother (and are shown with their ends facing one another) to engage oneof the plunger grooves 12. Note the plunger grooves 12 are shownextending circumferentially 360 degrees around the surface of theplunger 4. Thus, engagement of the arms 10 a, 10 b of the grooves is notdependent on the rotational position of the plunger 4 with respect tothe barrel 2. However, it is also contemplated that the grooves can beformed around less than 360 degrees around the outer surface of plunger4 and can be formed, for example, on opposing surfaces of the plunger 4such that each groove is engaged by one of the arms 10 a, 10 b.

The flexible structure 8 of the feedback mechanism 10 is attached to thebarrel 2 by various methods such as by welding. In this manner, theflexible structure can be attached to a standard barrel duringmanufacture rather than requiring designing an entire barrel. That is,the support 13 can be mounted and attached to a proximal end of thestandard barrel. Note the flexible structure can be an integral piece oralternatively can be composed of separate attached components such as acap (support) with openings through which each leg of the separate armcomponents extend and is attached. Each arm can also be a separate pieceattached to the support.

A rubber seal 6 can be provided, inserted into the barrel 2 andpositioned to prevent leakage of fluid from the barrel 2. The plunger 4would extend through seal 6.

The flexible arms 10 a, 10 b, by engaging a groove 12 of the pluralityof grooves, provide a tactile and/or audible indicator of the movementand position of the plunger 4. More specifically, as the plunger 4 isadvanced within barrel 2, the arms 10 a, 10 b engage one of the grooves12. Application of sufficient distal force on the plunger 4 willoverride the arm/groove engagement so the plunger 4 can be furtheradvanced to the next groove. This continues so the plunger can beadvanced step by step, i.e., in increments, with each step indicated tothe user by one or both of a tactile feel and an audible sound such asby a clicking noise as the arms 10 a, 10 b click into the groove 12. Itshould be appreciated that not only can the increments be adjusted byvarying the distance between grooves 12 as discussed above, but theforce required to advance the plunger 4 and thus the degree of tactilefeedback (and audible feedback) can also be adjusted. The force can beaffected by the depth of the grooves, the flexibility of the arms 10 a,10 b, the material of the arms 10 a, 10 b, the angle of the arms withrespect to the plunger grooves 12, or by other ways. For example, if thearms engage deeper grooves more force will be required and will provideincreased feedback (both tactile and audible). Less flexible arms andmore rigid material will also require more force and thus provideincreased feedback. It is also contemplated that the depth of thegrooves can vary along the length to provide different degrees offeedback if desired.

A specific example of arm modification to adjust the force required toadvance the plunger is shown, in the embodiment of FIGS. 37-39 whereinthe arms 74 a, 74 b of flexible structure 73 have a cutout 76 toincrease flexibility. This reduces the force requirement. Note more thanone cutout could be provided to further increase the flexibility. In allother respects, e.g., plunger 4 and barrel 72, the fluid dispensingdevice 71 is identical to the fluid dispensing device 11 of theembodiment of FIG. 1 and therefore for brevity, further discussion ofthe components is not provided since the description of the componentsand their function with regard to the embodiment of FIGS. 1-7 is fullyapplicable to the embodiment of FIGS. 37-39.

Turning back to FIGS. 1-7, in use, the user would remove from thepackage the syringe 11 which would contain the flexible structure 8 ofthe feedback mechanism 10 already attached. The barrel 2 can beprefilled or require filling after removal from the packaging. The userthen advances the plunger 4 distally within the barrel 2 until the userfeels a stop and/or hears a click. The physical stop felt by the user(as well as the click) is a result of engagement of the arms 10 a, 10 bwith one of the grooves 12. To dispense more fluid, the user advancesthe plunger 4 further distally, forcing the arms 10 a, 10 b out ofengagement with the groove 12 and sliding the plunger 4 until the arms10 a, 10 b engage the next plunger groove 12. This dispenses the nextamount of fluid, i.e., corresponding to the distance between the twogrooves. This continues until the user has delivered the desired amountof fluid from the syringe 11.

FIG. 8-13 illustrate an alternate embodiment of the fluid dispensingdevice (syringe) of the present invention. The fluid dispensing device21 is the same as fluid dispensing device 11 of FIGS. 1-7 except for theconfiguration of the flexible structure of the feedback mechanism.Therefore, dispensing device 11 has a plunger 4, plunger grooves 12formed in the plunger 4, needle 14 and seal 6 identical to that of fluiddispensing device 11 of FIGS. 1-7. Therefore, for brevity, furtherdiscussion of these components is not provided herein since thedescription of these components and their function with respect todispensing device 11 of FIGS. 1-7 is fully applicable to dispensingdevice 21 of FIGS. 8-13. As noted above, device 21 differs from device11 in the feedback mechanism 20.

Flexible structure 24 of feedback mechanism 20 is attached to barrel 22in manufacture by various methods such as welding. Flexible structure 24includes a pair of flexible elements or arms 24 a, 24 b. In theillustrated embodiment, the arms 24 a, 24 b extend from a cap or support27 which is attached in manufacture to a proximal end of barrel 22 sothe arms are external and proximal of barrel 22. Flexible arms 24 a, 24b are V-shaped, the vertex of the V extending toward the longitudinalaxis of the barrel 22. More specifically, the arms 24 a, 24 b have alongitudinal component extending proximally from a cap or support (base)27 at a proximal end portion of the barrel 22, then angle inwardly to avertex 25 a, 25 b, respectively, than angle outwardly away from thelongitudinal axis. The inward angle toward and away from the vertex asshown is about 40 degrees, however, other angles are also contemplated.The vertices 25 a, 25 b of arms 24 a, 24 b engage one of the grooves 12of the plunger 4. The vertices 25 a, 25 b extend toward one another (andare shown with their ends facing one another) to engage one of theplunger grooves 12. Thus, the arms 24 a, 24 b can be considered V-shapedwith a distal arm angled proximally inwardly and the proximal arm angleddistally inwardly to a vertex. In an alternate embodiment, the arms 24a, 24 b can be more U-shaped to have more curved arms and a vertex withmore curvature. Note the plunger grooves 12 are shown extendingcircumferentially 360 degrees around the surface of the plunger 4. Thus,engagement of the arms 24 a, 24 b of the grooves is not dependent on therotational position of the plunger 4 with respect to the barrel 2.However, it is also contemplated that the grooves can be formed on lessthan 360 degrees around the outer surface of plunger 4 and can beformed, for example, on opposing surfaces of the plunger 4 such thateach groove is engaged by one of the arms 24 a, 24 b.

The arms 24 a, 24 b, by engaging a groove of the plurality of grooves 12provide a tactile and/or audible indicator of the movement and positionof the plunger 4. More specifically, as the plunger 4 is advanced withinbarrel 22, the arms 24 a, 24 b engage one of the grooves 12 as thevertices 25 a, 25 b engage the groove 12. Application of sufficientforce on the plunger 4 will override the arm/groove engagement so theplunger 4 can be further advanced to the next groove. This continues sothe plunger 4 can be advanced step by step, i.e., in increments, witheach step indicated to the user by a tactile feel and/or by an audibleindicator such as by a clicking noise. It should be appreciated that aswith the embodiment of FIG. 1 (as well as the other embodimentsdiscussed herein) the increments can be adjusted by varying the distancebetween grooves 12. Thus, the distance between the grooves can begreater or less than shown in the illustrated embodiments to providegreater or less increments for delivery or larger or smaller doses offluid. Additionally, as with the embodiment of FIG. 1 discussed above(as well as the other embodiments discussed herein), the force requiredto advance the plunger 4 and thus the degree of tactile feedback canalso be adjusted. The force can be affected in various ways such as bythe depth of the grooves, the flexibility of the arms 24 a, 24 b, thematerial of the arms 24 a, 24 b, the angle of the arms, 24 a, 24 b,e.g., the angle of the V emanating from the vertex 25 a, 25 b, etc. Notethe arms could have an undercut (or additional cuts/removed material) toimprove flexibility (as in the embodiment of FIG. 37) formed for examplein a distal arm or in the longitudinal component of the arms.

In use, the user would remove from the package the syringe 21 whichwould contain the flexible structure 24 of the feedback mechanism 20already attached to the barrel 20. The barrel 20 can be prefilled orrequire filling after removed from the package. The user then advancesthe plunger 4 distally within the barrel 22 until the user feels a stopand/or hears a click. The physical stop felt by the user is a result ofengagement of the arms 24 a, 24 b with one of the grooves 12. Todispense more fluid, the user advances the plunger further distally,forcing the arms 24 a, 24 b (i.e., the vertices 25 a, 25 b) out ofengagement with the groove until they engage the next plunger groove.This dispenses the next amount of fluid, i.e., an amount in accordancewith the distance between the two grooves. This continues until the userhas delivered the desired amount of fluid from the syringe 21.

The configuration of the flexible structures disclosed herein, e.g.,flexible arms 10 a, 10 b and 25 a, 25 b, enhance flexibility tofacilitate fine increments of advancement. This is achieved based on oneor more factors. One factor is the arms are separated so that a proximalsurface of the arms are not contiguous, enabling independent movement ofthe arms. Additionally, the arms are configured so that both the distalportion and the proximal portion of the arm flex to provide moreflexibility as the arms are disengaged from the groove. Additionally, inpreferred embodiments, a distal portion of the arms flexes to a greaterdegree than the proximal portion as the arms are disengaged from thegroove, i.e., the deflection point (weaker portion) is closer to thebarrel. The arms in the disclosed embodiments deflect in a transversedirection (sideways action) rather than in an up and down direction todisengage from the groove. This results in the arms engaging the grooveas soon as it is aligned with the groove to provide a more efficientratchet type mechanism. It should also be appreciated in someembodiments a single arm rather than multiple arms can be utilized.

As noted above, the embodiments of FIGS. 1-13 provide a fluid dispensingdevice where the flexible structure of the feedback mechanism can beformed with the barrel. In the alternate embodiments of FIGS. 14-24, thefeedback mechanism is snap fit or otherwise attached to the barrel. Thisfacilitates manufacture as modular flexible structures can be readilyattached to a standard barrel. It is contemplated that the attachment ofthe feedback mechanism of the embodiment of FIGS. 14-24 to the barreloccurs during manufacture, however, it is also contemplated, in certainembodiments, that the flexible structure of the feedback mechanism canbe packaged or provided separately and snap fit or otherwise attached tothe barrel by the user post manufacture.

Turning first to the embodiment of FIGS. 14-18, the fluid dispensingdevice or syringe of this alternate embodiment is designated generallyby reference numeral 31. The fluid dispensing device 31 is the same asfluid dispensing device 11 of FIGS. 1-7 except for the flexiblestructure of the feedback mechanism. Therefore, dispensing device 31 hasa plunger 4, plunger grooves 12 formed in the outer surface of plunger4, needle 14 and seal 6 identical to that of fluid dispensing device 11of FIGS. 1-7. Therefore, for brevity, further discussion of thesecomponents is not provided herein since the description of thesecomponents and their function with respect to fluid dispensing device 11of FIGS. 1-7 is fully applicable to fluid dispensing device 31 of FIG.14-18.

As noted above, device 31 differs from device 11 in the feedbackmechanism 30. Flexible structure (mounting structure) 36 of feedbackmechanism 30 is attached to barrel 32 by a snap fit, although othermethods are contemplated such as by press fit, glue or ultrasoundwelding by way of example. Flexible structure 36, like flexiblestructure 8, has a pair of flexible arms 34 a, 34 b engageable withplunger grooves 12 as they bend inwardly toward the longitudinal axis ofthe device. Thus, the two arms 34 a, 34 b extend transversely toward oneanother (and are shown with their ends facing one another) to engage oneof the plunger grooves 12 in the same manner as arms 10 a, 10 b of FIGS.1-7.

The flexible structure 36 differs from flexible structure 8 by themounting to the barrel 32. More specifically, arms 34 a, 34 b offlexible structure 36 are somewhat U-shaped members with one leg, i.e.,the distal leg, of the U extending longitudinally from support ormounting cap 34, the base of the U extending longitudinally and theother leg, e.g., the proximal leg, extending transversely toward thelongitudinal axis to engage one of the grooves 12 on the plunger 4.Support 34 provides a snap attachment as distally extending flexibletabs or grips 38, spaced apart by about 180 degrees to be formed onopposing sides of the support 34, are snapped over proximal flange 33 ofbarrel 32 and engage an undersurface of flange 33 as shown in FIGS. 17and 18 to attach flexible structure 36 to the barrel 32. Note flange 33is at a proximal portion of the barrel 32 spaced distally from theproximalmost edge to provide a cylindrical region over which thefeedback mechanism (mounting/deflectable structure) is positioned as itis slid over the proximal end of the barrel 32. With the flange 33engaged, the feedback mechanism is effectively mounted to barrel 32.Note the mounting can be provided so as to be removable so that thefeedback mechanism 30 can subsequently be removed from barrel 32.Alternatively, the mounting can be provided such that once the feedbackmechanism 30 is attached to the barrel 32, it cannot be removed. Alsonote that other feedback mechanisms disclosed herein can be a separatestructure with flexible tabs to engage the underside of flange 33 tomount to the barrel 32. Note additional spaced tabs or grips 38 can beprovided to snap over flange 33.

Note the plunger grooves 12 are shown extending circumferentially 360degrees around the surface of the plunger 4. Thus engagement of the arms34 a, 34 b of the grooves is not dependent on the rotational position ofthe plunger 4 with respect to the barrel 32. However, it is alsocontemplated that the grooves can be formed on less than 360 degreesaround the outer surface of plunger 4 and can be formed, for example, onopposing surfaces of the plunger 4 such that each groove is engaged byone of the arms 34 a, 34 b.

The arms 34 a, 44 b, by engaging a groove of the plurality of grooves 12provide a tactile and/or audible indicator of the movement and positionof the plunger 4 in the same manner as described above with respect tothe embodiment of FIG. 1, i.e., engagement of the arms 34 a, 34 b withgrooves 12. Therefore, for brevity, further discussion of the arm/grooveengagement and use of the fluid dispensing device of FIGS. 14-18 willnot be provided since the discussion of the arm/groove engagement, thetactile and audible feedback and the use of the device 11 of theembodiment of FIG. 1 is fully applicable to fluid dispensing device 31of FIGS. 14-17. Additionally, the discussion above of adjustment of thedistances between grooves and adjustment of the force to adjust thetactile feedback is fully applicable to the embodiment of FIGS. 14-17.

It should be appreciated that it is contemplated that the flexiblestructure 34 be attached to the barrel 32 during manufacture. However,it is also contemplated that in certain embodiments the user orclinician (e.g., pharmacist) post manufacture can snap fit (or otherwiseattach) the flexible structure 36 to the barrel 32 if desired to providebetter controlled incremental advancement or for selective grooveengagement in the embodiments discussed below. In such use, the userwould remove from the package the flexible structure 36 and if desiredattach flexible structure 36 by pressing the structure over the proximalend of the barrel 32 until the flexible tabs 38 bypass and snap underflange 33. Thus, a kit can be provided containing the plunger, barreland mounting structure, e.g., flexible structure, for attachment to thebarrel.

An alternate embodiment of the fluid dispensing device or syringe isillustrated in FIGS. 19-24 and is designated generally by referencenumeral 41. The fluid dispensing device 41 is the same as fluiddispensing device 11 of FIGS. 1-7 except for the configuration of theflexible structure of the feedback mechanism. Therefore, dispensingdevice 41 has a plunger 4, plunger grooves 12 formed in the plunger 4,needle 14 and seal 6 identical to that of fluid dispensing device 11 ofFIGS. 1-7. Therefore, for brevity, further discussion of thesecomponents is not provided herein since the description of thesecomponents and their function with respect to dispensing device 11 ofFIGS. 1-7 is fully applicable to dispensing device 41 of FIG. 19-24.

As noted above, device 41 differs from device 11 in the feedbackmechanism 40. Flexible (mounting) structure 46 of feedback mechanism 40is attached to barrel 42 by a snap fit in the manner as described in theembodiment of FIGS. 14-18 (slid over the proximal region of the barrel),although other methods are contemplated such as by press fit, glue orultrasound welding by way of example. Flexible structure 46, likeflexible structure 24 of the embodiment of FIGS. 8-13, has a pair offlexible arms or elements 44 a, 44 b engageable with plunger grooves 12as they bend inwardly toward the longitudinal axis of the device. Theflexible arms 44 a, 44 b, like arms 24 a, 24 b are V-shaped, the vertexof the V extending toward the longitudinal axis of the barrel 42. Morespecifically, the arms 44 a, 44 b extend proximally from a cap orsupport 44, angle inwardly to a vertex 45 a, 45 b, respectively, thanangle outwardly away from the longitudinal axis of feedback mechanism40. The angle shown is about forty degrees, however, other angles arealso contemplated. The vertices 45 a, 45 b of arms 44 a, 44 b offeedback mechanism 40 engage one of the grooves 12 of the plunger 4. Thevertices 45 a, 45 b extend toward one another (and are shown with theirends facing one another) to engage one of the plunger grooves 12. Notethe plunger grooves 12 are shown extending circumferentially 360 degreesaround the surface of the plunger 4. Thus, engagement of the arms 44 a,44 b of the grooves is not dependent on the rotational position of theplunger 4 with respect to the barrel 2. However, it is also contemplatedthat the grooves can be formed less than 360 degrees around the outersurface of plunger 4 and can be formed, for example, on opposingsurfaces of the plunger 4 such that each groove is engaged by one of thearms 44 a 44 b.

The flexible structure 46 differs from flexible structure 24 of FIGS.8-13 due to the mounting to the barrel 42. More specifically, arms 44 a,44 b extend from support 44 which provides a snap attachment as flexibletabs or snapping grips 48, spaced apart by about 180 degrees to beformed on opposing sides of the support 44, are snapped over proximalflange 43 of barrel 42 and engage an undersurface of flange 43 as shownin FIGS. 22 and 23 in the same manner as in FIGS. 17 and 18 to attachflexible structure 46 to the barrel 42. (Note additional spaced tabscould also be provided).

The arms 44 a, 44 b, by engaging a groove of the plurality of grooves 12provide a tactile and/or audible indicator of the movement and positionof the plunger 4 in the same manner as described above with respect tothe embodiment of FIG. 1, i.e., engagement of the arms 44 a, 44 b withgrooves 12. Therefore, for brevity, further discussion of the arm/grooveengagement and use of the fluid dispensing device of FIGS. 19-24 willnot be provided since the discussion of the arm/groove engagement, thetactile and audible feedback and the use of the device 11 of theembodiment of FIG. 1 is fully applicable to fluid dispensing device 41of FIGS. 19-24. Additionally, discussion above of adjustment of thedistances between grooves and adjustment of the force to adjust thetactile feedback is fully applicable to the embodiment of FIGS. 19-24.

It should be appreciated that it is contemplated that the flexiblestructure 46 be attached to the barrel 42 during manufacture. However,it is also contemplated that in certain embodiments the user orclinician (e.g., pharmacist) post manufacture can snap fit (or otherwiseattach) the flexible structure 46 to the barrel 42 if desired to providebetter controlled incremental advancement. In such use, the user wouldremove from the package the flexible structure 46 and if desired attachflexible structure 46 by pressing the structure over the proximal end ofthe barrel 42 until the tabs 48 bypass and snap under flange 43. Thus,as in the embodiment of FIG. 14, a kit containing the plunger, barreland mounting structure can be provided.

FIGS. 25-36 illustrate an alternate embodiment of the fluid dispensingdevice (syringe) wherein the user has the option to select either a) theincremental injection of fluid and feedback mechanism as in theaforedescribed embodiments; or b) smooth continuous injection without anarm/groove engagement as in a standard syringe. This is achieved byproviding a plunger with grooves extending along only a portion of thecircumference so that the arms of the flexible structure are not alwaysengageable with the grooves.

More specifically, the fluid dispensing device (syringe) of FIGS. 25-36is designated generally by reference numeral 51 and includes a barrel52, a plunger 54 and a feedback mechanism 50. Penetrating needle 55extends distally from a distal end of the barrel 52 in the same manneras needle 14 of FIG. 1. The barrel 52 includes a lumen formed therein toreceive fluid for delivering to a patient and external markings 52 aformed along its entire, or alternatively its partial, length to providea visual indication to the user of the amount of fluid contained withinthe barrel 52. The plunger 54 is received in barrel 52 for axiallyslidable movement distally to dispense the fluid from the barrel 52. Aseal 6 identical to seal 6 of FIG. 1 can be positioned in a proximalportion of barrel 52. The fluid dispensing device 51 has twopositions: 1) an engagement position wherein the flexible structure 66of the feedback mechanism 50 engages plunger grooves 64; and 2) anon-engagement position wherein the flexible structure 66 does notengage the plunger grooves 64. These two positions are determined by therotational position of the plunger 54 relative to the barrel 52 asdiscussed in detail below. In the engagement position, a tactile and/oraudible feedback is provided.

More specifically, plunger 54 has a cross-sectional configuration withtwo opposing curved walls 65 a, 65 b and two opposing flat walls 67 a,67 b, with each flat wall 67 a, 67 b joining curved walls 65 a, 65 b onopposing sides (see the cross-sectional view of FIG. 29). Formed withinthe curved walls 65 a, 65 b are a plurality of grooves 64. A first setof grooves 64 a are formed in an outer (external) surface of the wall 65a and a second set of grooves 64 b are formed in an outer (external)surface of the wall 65 b, a groove from one set radially aligned with agroove from the other set for engagement by the arms of the flexiblestructure 66. (Collectively grooves 64 a and 64 b are referred to asgrooves 64). The grooves 64 extend along the length of the curved walls65 a, 65 b, spaced apart at intervals or increments corresponding to theamount of fluid desired to be injected at each step of advancement ofthe plunger 54 within the barrel 52 in the same manner as describedabove. By placing the plunger grooves 64 on portions of the surface ofthe plunger 54 so they are radially spaced, the flats 67 a, 67 b providea gap to which the arms 66 a, 66 b of the flexible structure 66 do notengage. Thus, the rotational position of the plunger 54 with respect tobarrel 52 will determine if the feedback mechanism is engageable(operational) or not engageable (not operational). Consequently, theuser can select whether detectible/measurable incremental advancement(with tactile and/or audible feedback) is desirable. It should beappreciated that the flats 67 a, 67 b are formed to provide a reducedcross-sectional diameter (transverse) region to provide a gap betweenthe flexible arms 66 a, 66 b and plunger 54. Therefore, as can beappreciated, other plunger configurations other than flats are alsocontemplated, such as an oval cross-section, for example, to provide areduced cross sectional dimension along a minor diameter fornon-engagement of the arms and grooves and a larger cross-sectionaldiameter along a major diameter for engagement of the arms with thegrooves.

In the illustrated embodiment, the plunger grooves 64 are equidistantlyspaced apart to provide equal doses of fluid. However, it is alsocontemplated that in alternate embodiments, the spacing between groovescould be non-uniform to accommodate situations where it is desired toprovide larger or smaller doses at certain times during injection. Also,the distances between the grooves can be greater or less than thedistances shown in the Figures to provide variations on dosage delivery.Note that such variations are applicable to the grooves of each of theembodiments disclosed herein. Also note the grooves of each set areradially aligned due to the radial alignment of the tips of the arms 66a, 66 b. If the tips are not radially aligned, then the grooves of eachset would also not be radially aligned in order to accommodate the tips.

Turning to the feedback mechanism 50 of device 51, the feedbackmechanism includes a flexible structure 66 identical to flexiblestructure 13 of FIG. 3. That is, the flexible structure 66 includes apair of flexible arms 66 a, 66 b having a somewhat U-shapedconfiguration with the proximal legs of the U extending inwardly towardthe longitudinal axis and toward each other. For brevity, furtherdiscussion of the flexible structure construction and attachment tobarrel 52 is not provided herein as the discussion of the constructionand attachment of flexible structure 13, including its variations suchas being mountable to the barrel as in FIG. 16, is fully applicable tothe embodiment of FIGS. 25-36.

It should be appreciated that flexible structure 66 is one example of aflexible structure and feedback mechanism that can be used with thedispensing device 51 of FIGS. 25-36. The various flexible structuresdescribed herein such as structure 24 of FIGS. 8-13, or other flexiblestructures configured to engage the plunger grooves can also be utilizedto selectively engage or not engage the grooves.

Plunger 54 has an end cap or pressing surface (or button) 57 at aproximal end having two opposing alignment (position) tabs 56, alsoreferred to as alignment (position) indicators, on opposing sides of thecap 57 to indicate the rotational position of the plunger. Flexiblestructure 66 includes opposing alignment (position) tabs 58, alsoreferred to as alignment (position) indicators, on opposing sides of anupper surface thereof, cooperating with position tabs 56 of plunger 54.When the tabs 56 of end cap 57 are longitudinally aligned with tabs 58of flexible structure 66 on barrel 52 as in FIGS. 25-30, referred toherein as the aligned position, the arms 66 a, 66 b of the flexiblestructure 66 of the feedback mechanism 60 are engageable with theplunger grooves 64 of plunger 54. On the other hand, when the tabs 56are not aligned (out of phase) with tabs 58, referred to herein as thenon-aligned position, the arms 66 a, 66 b are not engageable with theplunger grooves 64 as shown in FIGS. 31-36. This occurs when the plunger54 is rotated 90 degrees from the aligned position, and can beunderstood by comparing the position shown in FIGS. 27 and 28 to theposition shown in FIGS. 33 and 34. In this non-aligned position, thearms 66 a, 66 b are no longer aligned with the curved walls 65 a, 65 bbut instead are aligned (oppose) with the flat walls 67 a, 67 b of theplunger 54 and therefore, due to the reduced diameter, a gap is formed(see FIG. 36) and the arms 66 a, 66 b do not engage the walls 67 a, 67 band allow for continuous smooth motion of the plunger 64 to inject thefluid from the barrel. It should be appreciated that FIGS. 25-36 show anexample of an alignment indicator to indicate the rotational position ofthe plunger 54 relative to barrel 52. Other indicators on the plungerand/or flexible structure/barrel to inform the user of the rotationalposition of the plunger relative to the barrel 52 are also contemplated.

In addition, in alternate embodiments, instead of rotational movement ofthe plunger 54 to determine arm/groove engagement, the flexiblestructure can be rotated or repositioned or otherwise adjusted to movethe flexible arms into or out of alignment with the plunger grooves toprovide the user with the option of engaging the feedback mechanism.

Turning now to the use of fluid dispensing device 51, if the userdecides to utilize the feedback mechanism 60 for controlled measureddispensing of fluid from the fluid dispensing device 51 by incrementaladvancement of plunger 54 as indicated by the tactile and/or audibleindicator, the plunger 54 is positioned so that position tabs 56 arealigned with the position tabs 58 on the flexible structure 66 on barrel52. With such alignment, when plunger 54 is advanced through the lumenof the barrel 52, the plunger grooves 64 are engaged by the flexiblearms 66 a, 66 b in the arm/groove engagement manner discussed above.This is because when aligned, the curved walls 65 a, 65 b containing thegrooves 64 are aligned with the ends (tips) of the proximal legs of thearms 66 a, 66 b. If the user does not wish to engage the feedbackmechanism 60 and desires smooth continuous injection, the user rotatesthe plunger 54, e.g., 90 degrees in either direction, to the position ofFIGS. 33 and 34 so that position tabs 56 on plunger 54 are not alignedwith position tabs 58 on the flexible structure 66. This is because inthis non-aligned position, the flat walls 67 a, 67 b not containing thegrooves 64 are aligned with the ends (tips) of the proximal legs of thearms 66 a, 66 b and are not engaged by the legs. Note the fluiddispensing device can be provided, e.g., packaged, with the plunger 54in the position of FIG. 25 or in the position of FIG. 31, and the userwould determine the necessity of rotation depending on its intended use.

It is contemplated that the user can adjust the rotational position ofplunger 54 before initiation of injection of fluid as well as during theinjection. For example, if the user wishes to initially provide smallinjections of the fluid (with the tactile and/or audible feedback) butthen wants to inject a continuous dose, the user can rotate the plunger54 as described above to move the grooves 64 out of alignment with thearms 66 a, 66 b. If incremental injections are then desired, the plungercan be rotated back to the aligned position so the arms 66 a, 66 b arealigned with grooves 64. This rotation to engaged and non-engagedpositions can be repeated multiple times if desired.

The flexible structure 66 of FIGS. 25-36 is shown by way of example asit should be appreciated that the other flexible structures disclosedherein, e.g., flexible structure 24 of FIGS. 8-13, can be utilized withthe rotational plunger embodiment of FIGS. 25-36. Additionally, otherflexible structures to interact with the plunger grooves can also beutilized.

In the alternate embodiment of FIGS. 40-47, the plunger 82 is rotatableto change its orientation in the same manner as plunger 54 of fluiddispensing device 51 of FIG. 25. However, in this embodiment, theplunger 82 is rotatable to change the increments of advancement of theplunger 82. More specifically, plunger 82 has a first set of grooves 84on opposing walls and a second set of grooves 85 on opposing walls. Thegrooves 84, 85 extend along a length (either the entire or partiallength) of the walls of the plunger 82. A radial gap is provided betweenthe grooves to separate the grooves. Each of the grooves 84 of the firstset of grooves 84 are spaced apart a first distance L 1 and each of thegrooves 85 of the second set of grooves 85 are spaced apart a seconddistance L2. As shown, distance L2 is greater than distance L1 so thatthe plunger 82 moves in larger increments when grooves 85 are engagedthan when grooves 84 are engaged. The plunger 82 can have the first setof grooves 84 on one curved surface and the second set of grooves on anopposing curved surface, with a gap between the grooves 84, 85.Consequently, in the embodiment of FIGS. 40-47, the user has the optionto select either a) the smaller incremental injection of fluid with theaccompanying tactile and/or audible feedback as shown in FIG. 46 or b) alarger incremental injection of fluid with the accompanying tactileand/or audible feedback as shown in FIG. 47. Thus, the rotationalposition of the plunger 82 with respect to barrel 52 will determinewhich grooves are engageable. Thus, the user can select whichdetectible/measurable incremental advancement is desirable with itsaccompanying tactile (and audible) feedback.

In all other respects, the fluid dispensing device of FIGS. 40-47 isidentical to fluid dispensing 11 of FIGS. 1-6. The fluid dispensingdevice (syringe) of FIGS. 40-47 includes a barrel 52 (only a portion ofwhich is shown) identical to barrel 52 of the embodiment of FIG. 25, aplunger 82 and a feedback mechanism 80. Feedback mechanism includes aflexible structure 66 with arms 66 a, 66 b identical to flexiblestructure 66 of FIG. 25 (and FIG. 1). That is, the flexible structure 66includes a pair of flexible arms 66 a, 66 b having a somewhat U-shapedconfiguration with the proximal legs of the U extending inwardly towardthe longitudinal axis and toward each other. For brevity, furtherdiscussion of the flexible structure construction and attachment tobarrel 52 is not provided herein as the discussion of the constructionand attachment of flexible structure 66 of FIG. 25, including itsvariations, is fully applicable to the embodiment of FIGS. 40-47. Noteonly a proximal region of the barrel is illustrated in FIGS. 40 and 41since the barrel 52 of these Figures is identical to the barrel 52 ofFIG. 25.

It should be appreciated that flexible structure 66 is one example of aflexible structure and feedback mechanism that can be used with thegroove selection device of FIGS. 40-47. The other flexible structuresdescribed herein such as structure 24 of FIGS. 8-13, or other flexiblestructures, can also be utilized.

A penetrating needle (not shown) extends distally from a distal end ofthe barrel 52 of FIGS. 40 and 41 in the same manner as needle 14 ofFIG. 1. The barrel 52, like the barrel 52 of FIG. 25, includes a lumenformed therein to receive fluid for delivering to a patient and externalmarkings formed along its length to provide a visual indication to theuser of the amount of fluid contained within the barrel, and the plunger82 is received in the barrel for axially slidable movement distally todispense the fluid from the barrel 52 in the manner described above. Aseal identical to seal 6 of FIG. 1 can be provided. As noted above, thefluid dispensing device of FIGS. 40-47 has two positions: 1) a firstposition wherein the flexible structure 66 of the feedback mechanism 80engages plunger grooves 84 (see FIGS. 46); and 2) a second positionwherein the flexible structure 66 of the feedback mechanism engages theplunger grooves 85 (see FIG. 47). These two positions are determined bythe rotational position of the plunger 84 relative to the barrel 52. Inboth positions, a tactile and/or audible feedback is provided.

To accommodate these two positions, the plunger 82 has a transversecross-sectional dimension as shown in FIG. 42 with grooves 84 on thecurved walls along one axis of the cross and grooves 85 on the curvedwalls along another axis of the cross, the two axes being perpendicular.

Further, in some embodiments, the plunger 82 can have flat walls orother reduced diameter feature between the curved walls containinggrooves 84 and 85 to provide a disengaged position of the plungergrooves and arms of the flexible structure to provide a continuousmotion as in a standard syringe (as in the flat walls of FIGS. 35 and36). Thus, the user would have a third option (a third rotationalposition of the plunger) to bypass the feedback mechanism as in theembodiment of FIGS. 25-36 wherein a gap is formed between the flexiblearms and flat walls so that the arms of the flexible structure would notengage the plunger. The plunger would have a cross-sectional dimensionto accommodate these three positions.

Additionally, the plunger can have sets of grooves with spacingdifferent than spacing L1, L2 of grooves 84, 85.

In the illustrated embodiment, the plunger grooves 84 and plungergrooves 85 are equidistantly spaced apart to provide equal doses offluid. However, it is also contemplated that in alternate embodiments,the spacing between grooves could be non-uniform to accommodatesituations where it is desired to provide larger or smaller doses atcertain times during injection. Also, the distances between the groovescan be greater or less than the distances shown in the Figures toprovide variations on dosage delivery. An example of spacing can be 0.1cc, 0.25 cc, 0.50 cc, etc. Note that such variations are applicable tothe grooves of each of the embodiments disclosed herein.

Plunger 82 has an end cap or pressing surface (or button) 87 at aproximal end having two opposing alignment (position) tabs or alignment(position) indicators 88 on opposing sides of the cap 87 to indicate therotational position of the plunger. Flexible structure 66 includesopposing alignment (position) tabs 58, on opposing sides of an uppersurface of the flexible structure, cooperating with position tabs 88 ofplunger 82. When the tabs 88 are longitudinally aligned with tabs 58 asin FIGS. 44 and 46, the arms 66 a, 66 b of the flexible structure 66 ofthe feedback mechanism 60 are engageable with the plunger grooves 84. Onthe other hand, when the tabs 88 are not aligned with tabs 58, i.e., areout of phase with tabs 58, the arms 66 a, 66 b are engageable with theplunger grooves 85 as shown in FIGS. 45 and 47. This occurs when theplunger 82 is rotated 90 degrees from the position shown in FIGS. 44 and46 to the position shown in FIGS. 45 and 47. Note an alignment tab canalso be provided to indicate the position of FIGS. 45 and 47. It shouldbe appreciated that FIGS. 40-47 show an example of an alignmentindicator to indicate the position of the plunger 82 relative to barrel52. Other indicators to inform the user of the rotational position ofthe plunger relative to the barrel 52 are also contemplated. Forexample, the plunger cap can be pad printed to indicate its pitch (orfor the embodiment of FIG. 25 to indicate engaged or non-engagedpositions).

The configuration of the grooves 84 and 85 could differ to provide adifferent tactile feel and/or different audible feedback, i.e.,engagement of the arms of the flexible structure of one set of groovesbeing louder than engagement with the other set of grooves, or one setof grooves providing more resistance than the other set of grooves tofacilitate the user differentiating between which set of grooves areengaged. The various ways to adjust the force required to advance theplunger discussed above are fully applicable to the embodiment of FIGS.40-47 as well as to the other embodiments described herein.

In use, if the user desires incremental advancement of the plunger 82for controlled measured dispensing of fluid from the syringe inaccordance with the groove distances L1, the plunger 82 is positioned sothat position tabs 88 are aligned with the position tabs 58 on theflexible structure 66 on barrel 52. With such alignment, when plunger 82is advanced through the lumen of the barrel, the plunger grooves 84 areengaged by the flexible arms 66 a, 66 b in the arm/groove engagementmanner discussed above. This is because when aligned, the curved wallscontaining the grooves 84 are aligned with the ends of the proximal legsof the arms 66 a, 66 b. If the user desires incremental advancement ofthe plunger for controlled measured dispensing of fluid from the syringein accordance with the groove distances L2 to provide larger dosages,the user rotates the plunger 82, e.g., 90 degrees in either direction,to the position of FIGS. 45 and 47 so that position tabs 88 are notaligned with tabs 58. In this position, when not aligned, the grooves 85are aligned with the ends of the proximal legs of the arms 66 a, 66 b.Note the device can be provided with the plunger in the position of FIG.46 or in the position of FIG. 47, and the user would determine thenecessity of rotation depending on its intended use.

It is contemplated that the user can adjust the rotational position ofplunger 82 before initiation of injection of fluid as well as during theinjection. For example, if the user wishes to initially provide smallinjections of the fluid but then wants to inject a dose or doses ofgreater increments, the user can rotate the plunger 82 as describedabove to move the grooves 85 into alignment with the arm 66 a, 66 b. Ifsmaller injections are then desired, the plunger 82 can be rotated backto the position so the arms 66 a, 66 b are aligned with grooves 84. Thisrotation between the two engaged positions can be repeated multipletimes if desired.

The flexible structure 66 of FIGS. 40-47 is shown by way of example asit should be appreciated that the other flexible structures disclosedherein, e.g., flexible structure 24, can be utilized with the rotationalplunger embodiment of FIGS. 40-47. Additionally, other flexiblestructures to interact with the plunger grooves can also be utilized.

In addition, in alternate embodiments, instead of rotational movement ofthe plunger 54 to determine arm/groove engagement, the flexiblestructure can be selectively rotated or repositioned or otherwiseadjusted to move the flexible arms into or out of alignment with theplunger grooves to provide the user with the selective engagement of thedesired feedback mechanism.

It is also contemplated that the feedback mechanism of FIGS. 40-47 canbe mountable to the barrel 52 in the same manner as in the embodiment ofFIG. 16.

FIGS. 37-47 illustrate an embodiment where different spacing of groovesprovides delivery of different increments and accompanying feedback. Inanother concept, rather than relying on rotation/reorientation of theplunger to provide the desired dosage indicator, the flexible structureis configured to provide such differentiation. For example, one of thearms of the flexible structure can have a first flexibility and theother arm can have a second flexibility. In this manner, the tactilefeel and audible click will also be different as one ratchet arm wouldbe stiffer and louder than the other to allow differentiation betweenthem. For example, assuming x units, e.g., 37 units, are required to beadministered. The smaller distance L1 can represent delivery of 1 unitincrements and the larger distance L2 could represent 5 unit increments.As the plunger is advanced, the user would hear and feel the 1 unitincrements but also feel the 5 mm increments since the flexiblestructure engagement with the grooves would differ. In this way, the 5mm increment ratchet would facilitate the user's count of theadministered dose. Note that the number of units and the increments areprovided by way of example as a different number of units and differentincrements are also contemplated.

It is also contemplated that in any of the embodiments disclosed herein,instead of two or more sets of grooves, a single set of grooves can beprovided that has variable feedback depending on groove configuration.For example, every 5^(th) or 10^(th) groove can be different, e.g., havea greater depth, so that every 5^(th) or 10^(th) click produces adifferent feedback than the other grooves to simplify counting when alarge number of clicks is provided. Note that 5^(th) and 10^(th) areused by way of example since other grooves, e.g., 3 rd, could bemodified to provide varying feedback at desired intervals.

In an alternate embodiment illustrated in FIGS. 53 and 54, amulti-ratchet configuration can be provided. If the desired incrementsto be applied are sufficiently small that it is difficult to attain witha single ratchet, a ratchet could be provided on each side of the barreland the plunger could have a first set of grooves separated by adistance X and a second set of grooves separated by a distance X, withthe grooves offset so that one ratchet would engage one set of groovesand the other ratchet would engage the other set of grooves. By way ofexample, the grooves can be separated by a distance of 2 mm and have anoffset of 1 mm so that 1 mm increments can be attained. As shown,plunger 100 has a first set of grooves 102 and a second set of grooves103 longitudinally offset. In FIG. 52, arm 106 of deflectable structure104 engages a groove of the first set of grooves 102 and arm 108 is notengaged with a groove of the second set of grooves 103. When the plunger100 is further advanced to the position of FIG. 53, arm 106 ofdeflectable structure 104 does not engage a groove of the first set ofgrooves 102 and arm 108 engages a groove of the second set of grooves103. This enables tiny injections to be applied since the minimumspacing of the grooves is limited by a minimum depth/height of a groovenecessary to provide detectable feedback, and such offset allows forsufficiently sized grooves in minimally spaced increments along theplunger. Note any of the foregoing deflectable structures, including themountable structures, can be utilized with the embodiment of FIGS. 53and 54. Additionally, the first and second sets of grooves could havedifferent spacing between the grooves.

In another alternate embodiment, a plunger cross-shaped in transversecross-section could have grooves of different spacing on each of thefour wings (walls). By way of example, the wings could have incrementscorresponding to 0.1, 0.2. 0.25 and 0.5 cc. Note that other incrementsare also contemplated, the foregoing provided by way of example. Eachwing would be pad-printed to indicate its pitch. The snap on attachment,i.e., the attachable flexible (mounting) structure would have anorientation feature so that its flexible arm would be set to engage witha single wing. One way this can be achieved is by providing the plungerwith a cross-shaped cross section, or other asymmetrical cross-section,wherein each wing of the cross has a slightly different dimension orconfiguration. The flexible structure has an opening conforming to thewing shape and thus could only be placed in a single orientation. Inthis manner, a user would select the modular flexible structure for thedesired orientation and attach the flexible structure to the barrel sothat the flexible arm is oriented to engage only the grooves on theselected wing of the cross-shaped plunger. Thus, the assembler of thesyringe would select the flexible structure from a set of flexiblestructures and mount it to the barrel so its flexible arm engages thedesired wing of the plunger for administering the desired fluidincrements. Note that the assembler of the various embodiments of thesyringes disclosed herein could be by the manufacturer who would mountthe modular flexible structures to barrels in various orientations toprovide assembled syringes with select dosage increments. The assemblerof the various embodiments of the syringes disclosed herein could alsobe the hospital pharmacist who can customize the syringes by orientationof the flexible structures received from the manufacturer.

In alternate embodiments, the flexible structure of any of theembodiments disclosed herein can be removably mounted to the barrel sothe user can remove it from the barrel to disengage the feedbackmechanism and controlled incremental advancement.

It should be appreciated that the flexible structures/groove engagementdisclosed herein provide one form of ratchet to provide the feedbackmechanisms. Other flexible structures and arm configurations to performthe ratcheting function are also contemplated.

It should also be appreciated that although the grooves of the foregoingembodiments are located on the plunger and the flexible engagingelements are attached or extend from the barrel, it is also contemplatedin any of the foregoing embodiments that the groove/flexible elementarrangement is reversed so that the flexible element is on the plungerand extends transversely therefrom and the barrel has one or more setsof grooves along part of or along its entire length. In this way, as theplunger is advanced within the barrel, the flexible elements of theplunger will engage the various grooves of the barrel and provide theincremental doses and the tactile and/or audible indication in the samemanner as the when the plunger has the grooves and the barrel has theflexible elements as described in detail above. Instead of grooves, thebarrel can have a rigid structure engaging the flexible elements of theplunger.

FIGS. 48-52 provide one example of an arrangement wherein plunger 90 hasthe flexible elements and the barrel has the rigid element (s). Morespecifically, plunger 90 has flexible lips or ribs axially spaced aroundthe circumferential surface of plunger 90. Barrel 94 has a lip structure96 and ribs 98 which make lip structure non-flexible (rigid). Whenflexible lips 92 engage with the rigid structure 96 they provide atactile and/or audible feedback to the user. Note that the outsidediameter of the lips 92 is preferably smaller than the inner diameter ofthe barrel 94 to avoid additional frictional resistance during movementof the plunger 90 within the barrel 92.

The pressing surface of the plungers disclosed herein could havedifferent configurations such as a small flat button, a finger ring or alarge surface button to ergonomically accommodate clinical applicationsthat require exertion of higher pressure. In some embodiments, suchpressing surface can be a snap on button which can be non-removablyattached to the plunger, or alternatively, removably attached to theplunger, during manufacture or by a user. This would facilitate assemblyas the flexible structure could be placed on the barrel after thesyringe is positioned in the barrel. For example, the hospitalpharmacist would receive from the manufacturer the plunger positioned inthe barrel and a separate flexible structure and pressing surface. Thepharmacist could select the desired flexible structure for the desiredorientation of the flexible structure and slide it over the plunger andonto the barrel for snap fitting onto the barrel. The pressing surface(cap) for the plunger could then be applied.

While the above description contains many specifics, those specificsshould not be construed as limitations on the scope of the disclosure,but merely as exemplifications of preferred embodiments thereof. Thoseskilled in the art will envision many other possible variations that arewithin the scope and spirit of the disclosure as defined by the claimsappended hereto.

What is claimed is:
 1. A fluid dispensing device comprising: a barrelhaving a lumen for containing a fluid therein and a flexible structureextending from the barrel; and a plunger axially slidable within thelumen to dispense fluid from the barrel, the plunger having a first setof grooves spaced apart a first distance and a second set of groovesspaced apart a second distance, and the flexible structure including atleast one flexible arm extending transversely with respect to the barreland positioned to engage either the first set of grooves or the secondset of grooves.
 2. The device of claim 1, wherein the flexible structureare selectively mountable to the barrel.
 3. The device of claim 1,wherein the plunger has an asymmetric transverse cross-sectional shapehaving a first wall and a second wall, the first set of grooves formedon the first wall and the second set of grooves formed on the secondwall.
 4. The device of claim 1, wherein the flexible structure issnapped onto the barrel.
 5. The device of claim 1, wherein the flexiblestructure has an indicator to inform the user of which set of groovesthe flexible arm will engage.
 6. The device of claim 2, wherein theplunger has a first position wherein the flexible structure isengageable with grooves of the first set of grooves when the plunger isadvanced through the barrel to dispense first increments of fluid and asecond position wherein the flexible structure is engageable withgrooves of the second set of grooves when the plunger is advancedthrough the barrel to dispense second increments of fluid.
 7. The deviceof claim 1, wherein engagement of the flexible structure with one of thegrooves provides one or both of a tactile indication and audibleindication to a user.
 8. The device of claim 6, wherein the plunger isselectively mountable to the barrel in an orientation to only align witheither the first set of grooves or the second set of grooves.
 9. Thedevice of claim 1, wherein the plunger has a first orientation and asecond orientation, wherein a) in the first orientation the flexiblestructure is engageable with the first set of grooves and the second setof grooves when the plunger is advanced axially within the barrel and b)in the second orientation the flexible structure is not engageable withthe first set of grooves or the second set of grooves when the plungeris advanced axially through the barrel.
 10. The device of claim 1,wherein engagement with of the flexible structure with the first set ofgrooves provides a first feedback and engagement of the flexiblestructure with the second set of grooves provides a second feedback moreprominent than the first feedback.
 11. The device of claim 1, whereinthe flexible structure includes a pair of transversely extendingflexible arms, the flexible arms engageable with the grooves, the firstarm having a first stiffness to provide the first feedback and thesecond arm having a second stiffness to provide the second feedback. 12.A fluid dispensing device comprising: a barrel having a lumen forcontaining a fluid therein and a deflectable structure extending fromthe barrel; and a plunger axially slidable within the lumen to dispensefluid from the barrel, the plunger having a longitudinal axis and a setof grooves extending longitudinally along an outer surface, thedeflectable structure extending transversely with respect to the barreland positioned to engage the set of grooves, the deflectable structuredeflecting in a transverse direction to disengage from the grooves. 13.The device of claim 12, wherein the deflectable structure is engageablewith the groove as soon as the flexible structure is aligned with thegroove.
 14. The device of claim 12, wherein the flexible structureincludes a first arm having one of a U-shaped configuration or aV-shaped configuration wherein a vertex of the U or V-shape isengageable with the groove.
 15. The device of claim 12, wherein theflexible arm has a longitudinally extending portion and a transverselyextending portion, the longitudinally extending portion deflecting to agreater extent than the transversely extending portion.
 16. The deviceof claim 12, wherein the deflectable structure includes first and secondarms, the first arm having a first proximal surface and the second armhaving a second proximal surface, the first and second arms spaced apartso that the first and second proximal surfaces are not contiguous. 17.The device of claim 16, wherein the first arm is configured such that adistal portion deflects to a greater degree than a proximal portion asthe first flexible arm disengages from the groove and the second arm isconfigured such that a second distal portion deflects to a greaterdegree than a second proximal portion as the second flexible armdisengages from the groove.
 18. A fluid dispensing device comprising: abarrel having a lumen for containing a fluid therein and a flange at aproximal portion of the barrel; a plunger axially slidable within thelumen to dispense fluid from the barrel, the plunger having alongitudinal axis and a set of grooves extending longitudinally along anouter surface, and a deflectable structure mountable to the proximalportion of the barrel and engageable with an underside of the flange,the deflectable structure extending transversely with respect to thebarrel and positioned to engage the set of grooves, the deflectablestructure being external of the barrel and exposed.
 19. The device ofclaim 18, further comprising a pressing button for engagement by a userto advance the plunger, the pressing button mountable to the plungerafter the deflectable structure is mounted over the plunger forattachment to the barrel.
 20. The device of claim 18, wherein thedeflectable structure is mountable to the barrel only in a singlerotational orientation.